Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.654
Filtrar
Más filtros

Intervalo de año de publicación
1.
Cell ; 186(21): 4632-4651.e23, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37776858

RESUMEN

The dynamics of immunity to infection in infants remain obscure. Here, we used a multi-omics approach to perform a longitudinal analysis of immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in infants and young children by analyzing blood samples and weekly nasal swabs collected before, during, and after infection with Omicron and non-Omicron variants. Infection stimulated robust antibody titers that, unlike in adults, showed no sign of decay for up to 300 days. Infants mounted a robust mucosal immune response characterized by inflammatory cytokines, interferon (IFN) α, and T helper (Th) 17 and neutrophil markers (interleukin [IL]-17, IL-8, and CXCL1). The immune response in blood was characterized by upregulation of activation markers on innate cells, no inflammatory cytokines, but several chemokines and IFNα. The latter correlated with viral load and expression of interferon-stimulated genes (ISGs) in myeloid cells measured by single-cell multi-omics. Together, these data provide a snapshot of immunity to infection during the initial weeks and months of life.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Niño , Lactante , Humanos , Preescolar , SARS-CoV-2/metabolismo , Multiómica , Citocinas/metabolismo , Interferón-alfa , Inmunidad Mucosa
2.
Immunity ; 54(4): 753-768.e5, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33765435

RESUMEN

Viral infections induce a conserved host response distinct from bacterial infections. We hypothesized that the conserved response is associated with disease severity and is distinct between patients with different outcomes. To test this, we integrated 4,780 blood transcriptome profiles from patients aged 0 to 90 years infected with one of 16 viruses, including SARS-CoV-2, Ebola, chikungunya, and influenza, across 34 cohorts from 18 countries, and single-cell RNA sequencing profiles of 702,970 immune cells from 289 samples across three cohorts. Severe viral infection was associated with increased hematopoiesis, myelopoiesis, and myeloid-derived suppressor cells. We identified protective and detrimental gene modules that defined distinct trajectories associated with mild versus severe outcomes. The interferon response was decoupled from the protective host response in patients with severe outcomes. These findings were consistent, irrespective of age and virus, and provide insights to accelerate the development of diagnostics and host-directed therapies to improve global pandemic preparedness.


Asunto(s)
Inmunidad/genética , Virosis/inmunología , Presentación de Antígeno/genética , Estudios de Cohortes , Hematopoyesis/genética , Humanos , Interferones/sangre , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/patología , Células Mieloides/inmunología , Células Mieloides/patología , Pronóstico , Índice de Severidad de la Enfermedad , Biología de Sistemas , Transcriptoma , Virosis/sangre , Virosis/clasificación , Virosis/genética , Virus/clasificación , Virus/patogenicidad
3.
Nature ; 625(7995): 516-522, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38233617

RESUMEN

Perovskite solar cells (PSCs) comprise a solid perovskite absorber sandwiched between several layers of different charge-selective materials, ensuring unidirectional current flow and high voltage output of the devices1,2. A 'buffer material' between the electron-selective layer and the metal electrode in p-type/intrinsic/n-type (p-i-n) PSCs (also known as inverted PSCs) enables electrons to flow from the electron-selective layer to the electrode3-5. Furthermore, it acts as a barrier inhibiting the inter-diffusion of harmful species into or degradation products out of the perovskite absorber6-8. Thus far, evaporable organic molecules9,10 and atomic-layer-deposited metal oxides11,12 have been successful, but each has specific imperfections. Here we report a chemically stable and multifunctional buffer material, ytterbium oxide (YbOx), for p-i-n PSCs by scalable thermal evaporation deposition. We used this YbOx buffer in the p-i-n PSCs with a narrow-bandgap perovskite absorber, yielding a certified power conversion efficiency of more than 25%. We also demonstrate the broad applicability of YbOx in enabling highly efficient PSCs from various types of perovskite absorber layer, delivering state-of-the-art efficiencies of 20.1% for the wide-bandgap perovskite absorber and 22.1% for the mid-bandgap perovskite absorber, respectively. Moreover, when subjected to ISOS-L-3 accelerated ageing, encapsulated devices with YbOx exhibit markedly enhanced device stability.

4.
Cell ; 158(6): 1431-1443, 2014 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-25215497

RESUMEN

Transcription factor (TF) DNA sequence preferences direct their regulatory activity, but are currently known for only ∼1% of eukaryotic TFs. Broadly sampling DNA-binding domain (DBD) types from multiple eukaryotic clades, we determined DNA sequence preferences for >1,000 TFs encompassing 54 different DBD classes from 131 diverse eukaryotes. We find that closely related DBDs almost always have very similar DNA sequence preferences, enabling inference of motifs for ∼34% of the ∼170,000 known or predicted eukaryotic TFs. Sequences matching both measured and inferred motifs are enriched in chromatin immunoprecipitation sequencing (ChIP-seq) peaks and upstream of transcription start sites in diverse eukaryotic lineages. SNPs defining expression quantitative trait loci in Arabidopsis promoters are also enriched for predicted TF binding sites. Importantly, our motif "library" can be used to identify specific TFs whose binding may be altered by human disease risk alleles. These data present a powerful resource for mapping transcriptional networks across eukaryotes.


Asunto(s)
Arabidopsis/genética , Motivos de Nucleótidos , Análisis de Secuencia de ADN , Factores de Transcripción/metabolismo , Arabidopsis/metabolismo , Inmunoprecipitación de Cromatina , Humanos , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Unión Proteica , Sitios de Carácter Cuantitativo
5.
Nature ; 618(7965): 583-589, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37286596

RESUMEN

Bacteroidetes are abundant members of the human microbiota, utilizing a myriad of diet- and host-derived glycans in the distal gut1. Glycan uptake across the bacterial outer membrane of these bacteria is mediated by SusCD protein complexes, comprising a membrane-embedded barrel and a lipoprotein lid, which is thought to open and close to facilitate substrate binding and transport. However, surface-exposed glycan-binding proteins and glycoside hydrolases also play critical roles in the capture, processing and transport of large glycan chains. The interactions between these components in the outer membrane are poorly understood, despite being crucial for nutrient acquisition by our colonic microbiota. Here we show that for both the levan and dextran utilization systems of Bacteroides thetaiotaomicron, the additional outer membrane components assemble on the core SusCD transporter, forming stable glycan-utilizing machines that we term utilisomes. Single-particle cryogenic electron microscopy structures in the absence and presence of substrate reveal concerted conformational changes that demonstrate the mechanism of substrate capture, and rationalize the role of each component in the utilisome.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa , Membrana Externa Bacteriana , Bacteroides thetaiotaomicron , Tracto Gastrointestinal , Polisacáridos , Humanos , Membrana Externa Bacteriana/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Bacteroides thetaiotaomicron/enzimología , Bacteroides thetaiotaomicron/metabolismo , Tracto Gastrointestinal/metabolismo , Tracto Gastrointestinal/microbiología , Glicósido Hidrolasas/metabolismo , Polisacáridos/metabolismo
6.
Nature ; 618(7963): 74-79, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36977463

RESUMEN

The tunable bandgaps and facile fabrication of perovskites make them attractive for multi-junction photovoltaics1,2. However, light-induced phase segregation limits their efficiency and stability3-5: this occurs in wide-bandgap (>1.65 electron volts) iodide/bromide mixed perovskite absorbers, and becomes even more acute in the top cells of triple-junction solar photovoltaics that require a fully 2.0-electron-volt bandgap absorber2,6. Here we report that lattice distortion in iodide/bromide mixed perovskites is correlated with the suppression of phase segregation, generating an increased ion-migration energy barrier arising from the decreased average interatomic distance between the A-site cation and iodide. Using an approximately 2.0-electron-volt rubidium/caesium mixed-cation inorganic perovskite with large lattice distortion in the top subcell, we fabricated all-perovskite triple-junction solar cells and achieved an efficiency of 24.3 per cent (23.3 per cent certified quasi-steady-state efficiency) with an open-circuit voltage of 3.21 volts. This is, to our knowledge, the first reported certified efficiency for perovskite-based triple-junction solar cells. The triple-junction devices retain 80 per cent of their initial efficiency following 420 hours of operation at the maximum power point.

7.
Nature ; 611(7935): 387-398, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36289338

RESUMEN

Acute myeloid leukaemia (AML) represents a set of heterogeneous myeloid malignancies, and hallmarks include mutations in epigenetic modifiers, transcription factors and kinases1-5. The extent to which mutations in AML drive alterations in chromatin 3D structure and contribute to myeloid transformation is unclear. Here we use Hi-C and whole-genome sequencing to analyse 25 samples from patients with AML and 7 samples from healthy donors. Recurrent and subtype-specific alterations in A/B compartments, topologically associating domains and chromatin loops were identified. RNA sequencing, ATAC with sequencing and CUT&Tag for CTCF, H3K27ac and H3K27me3 in the same AML samples also revealed extensive and recurrent AML-specific promoter-enhancer and promoter-silencer loops. We validated the role of repressive loops on their target genes by CRISPR deletion and interference. Structural variation-induced enhancer-hijacking and silencer-hijacking events were further identified in AML samples. Hijacked enhancers play a part in AML cell growth, as demonstrated by CRISPR screening, whereas hijacked silencers have a downregulating role, as evidenced by CRISPR-interference-mediated de-repression. Finally, whole-genome bisulfite sequencing of 20 AML and normal samples revealed the delicate relationship between DNA methylation, CTCF binding and 3D genome structure. Treatment of AML cells with a DNA hypomethylating agent and triple knockdown of DNMT1, DNMT3A and DNMT3B enabled the manipulation of DNA methylation to revert 3D genome organization and gene expression. Overall, this study provides a resource for leukaemia studies and highlights the role of repressive loops and hijacked cis elements in human diseases.


Asunto(s)
Genoma Humano , Leucemia Mieloide Aguda , Humanos , Cromatina/genética , Metilación de ADN , Leucemia Mieloide Aguda/genética , Genoma Humano/genética , Regiones Promotoras Genéticas , Elementos de Facilitación Genéticos , Silenciador del Gen , Reproducibilidad de los Resultados , Sistemas CRISPR-Cas , Análisis de Secuencia , ADN (Citosina-5-)-Metiltransferasas , Regulación Leucémica de la Expresión Génica
8.
Nature ; 599(7886): 594-598, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34819678

RESUMEN

Light-emitting diodes (LEDs) based on perovskite quantum dots have shown external quantum efficiencies (EQEs) of over 23% and narrowband emission, but suffer from limited operating stability1. Reduced-dimensional perovskites (RDPs) consisting of quantum wells (QWs) separated by organic intercalating cations show high exciton binding energies and have the potential to increase the stability and the photoluminescence quantum yield2,3. However, until now, RDP-based LEDs have exhibited lower EQEs and inferior colour purities4-6. We posit that the presence of variably confined QWs may contribute to non-radiative recombination losses and broadened emission. Here we report bright RDPs with a more monodispersed QW thickness distribution, achieved through the use of a bifunctional molecular additive that simultaneously controls the RDP polydispersity while passivating the perovskite QW surfaces. We synthesize a fluorinated triphenylphosphine oxide additive that hydrogen bonds with the organic cations, controlling their diffusion during RDP film deposition and suppressing the formation of low-thickness QWs. The phosphine oxide moiety passivates the perovskite grain boundaries via coordination bonding with unsaturated sites, which suppresses defect formation. This results in compact, smooth and uniform RDP thin films with narrowband emission and high photoluminescence quantum yield. This enables LEDs with an EQE of 25.6% with an average of 22.1 ±1.2% over 40 devices, and an operating half-life of two hours at an initial luminance of 7,200 candela per metre squared, indicating tenfold-enhanced operating stability relative to the best-known perovskite LEDs with an EQE exceeding 20%1,4-6.

9.
J Immunol ; 212(4): 737-747, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38169329

RESUMEN

Epigenetic regulation plays a crucial role in the development and progression of cancer, including the regulation of antitumor immunity. The reversible nature of epigenetic modifications offers potential therapeutic avenues for cancer treatment. In particular, histone deacetylase (HDAC) inhibitors (HDACis) have been shown to promote antitumor T cell immunity by regulating myeloid cell types, enhancing tumor Ag presentation, and increasing expression of chemokines. HDACis are currently being evaluated to determine whether they can increase the response rate of immune checkpoint inhibitors in cancer patients. Although the potential direct effect of HDACis on T cells likely impacts antitumor immunity, little is known about how HDAC inhibition alters the transcriptomic profile of T cells. In this article, we show that two clinical-stage HDACis profoundly impact gene expression and signaling networks in CD8+ and CD4+ T cells. Specifically, HDACis promoted T cell effector function by enhancing expression of TNF-α and IFN-γ and increasing CD8+ T cell cytotoxicity. Consistently, in a murine tumor model, HDACis led to enrichment of CD8+ T cell subsets with high expression of effector molecules (Prf1, Ifng, Gzmk, and Grmb) but also molecules associated with T cell exhaustion (Tox, Pdcd1, Lag3, and Havcr2). HDACis further generated a tumor microenvironment dominated by myeloid cells with immune suppressive signatures. These results indicate that HDACis directly and favorably augment T cell effector function but also increase their exhaustion signal in the tumor microenvironment, which may add a layer of complexity for achieving clinical benefit in combination with immune checkpoint inhibitors.


Asunto(s)
Inhibidores de Histona Desacetilasas , Neoplasias , Humanos , Animales , Ratones , Inhibidores de Histona Desacetilasas/farmacología , Epigénesis Genética , Inhibidores de Puntos de Control Inmunológico/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Linfocitos T CD8-positivos , Expresión Génica , Microambiente Tumoral
10.
PLoS Genet ; 19(11): e1011008, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37930961

RESUMEN

The cuticles of ecdysozoan animals are barriers to material loss and xenobiotic insult. Key to this barrier is lipid content, the establishment of which is poorly understood. Here, we show that the p-glycoprotein PGP-14 functions coincidently with the sphingomyelin synthase SMS-5 to establish a polar lipid barrier within the pharyngeal cuticle of the nematode C. elegans. We show that PGP-14 and SMS-5 are coincidentally expressed in the epithelium that surrounds the anterior pharyngeal cuticle where PGP-14 localizes to the apical membrane. pgp-14 and sms-5 also peak in expression at the time of new cuticle synthesis. Loss of PGP-14 and SMS-5 dramatically reduces pharyngeal cuticle staining by Nile Red, a key marker of polar lipids, and coincidently alters the nematode's response to a wide-range of xenobiotics. We infer that PGP-14 exports polar lipids into the developing pharyngeal cuticle in an SMS-5-dependent manner to safeguard the nematode from environmental insult.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Membrana Celular/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Lípidos , Permeabilidad
11.
N Engl J Med ; 386(9): 827-836, 2022 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-35235725

RESUMEN

BACKGROUND: Consensus recommendations regarding the threshold levels of cardiac troponin elevations for the definition of perioperative myocardial infarction and clinically important periprocedural myocardial injury in patients undergoing cardiac surgery range widely (from >10 times to ≥70 times the upper reference limit for the assay). Limited evidence is available to support these recommendations. METHODS: We undertook an international prospective cohort study involving patients 18 years of age or older who underwent cardiac surgery. High-sensitivity cardiac troponin I measurements (upper reference limit, 26 ng per liter) were obtained 3 to 12 hours after surgery and on days 1, 2, and 3 after surgery. We performed Cox analyses using a regression spline that explored the relationship between peak troponin measurements and 30-day mortality, adjusting for scores on the European System for Cardiac Operative Risk Evaluation II (which estimates the risk of death after cardiac surgery on the basis of 18 variables, including age and sex). RESULTS: Of 13,862 patients included in the study, 296 (2.1%) died within 30 days after surgery. Among patients who underwent isolated coronary-artery bypass grafting or aortic-valve replacement or repair, the threshold troponin level, measured within 1 day after surgery, that was associated with an adjusted hazard ratio of more than 1.00 for death within 30 days was 5670 ng per liter (95% confidence interval [CI], 1045 to 8260), a level 218 times the upper reference limit. Among patients who underwent other cardiac surgery, the corresponding threshold troponin level was 12,981 ng per liter (95% CI, 2673 to 16,591), a level 499 times the upper reference limit. CONCLUSIONS: The levels of high-sensitivity troponin I after cardiac surgery that were associated with an increased risk of death within 30 days were substantially higher than levels currently recommended to define clinically important periprocedural myocardial injury. (Funded by the Canadian Institutes of Health Research and others; VISION Cardiac Surgery ClinicalTrials.gov number, NCT01842568.).


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Infarto del Miocardio/diagnóstico , Complicaciones Posoperatorias/diagnóstico , Troponina I/sangre , Anciano , Válvula Aórtica/cirugía , Biomarcadores/sangre , Procedimientos Quirúrgicos Cardíacos/mortalidad , Puente de Arteria Coronaria/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/etiología , Infarto del Miocardio/mortalidad , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/mortalidad , Estudios Prospectivos , Valores de Referencia
12.
PLoS Biol ; 20(4): e3001615, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35476669

RESUMEN

Understanding the regulatory interactions that control gene expression during the development of novel tissues is a key goal of evolutionary developmental biology. Here, we show that Mbnl3 has undergone a striking process of evolutionary specialization in eutherian mammals resulting in the emergence of a novel placental function for the gene. Mbnl3 belongs to a family of RNA-binding proteins whose members regulate multiple aspects of RNA metabolism. We find that, in eutherians, while both Mbnl3 and its paralog Mbnl2 are strongly expressed in placenta, Mbnl3 expression has been lost from nonplacental tissues in association with the evolution of a novel promoter. Moreover, Mbnl3 has undergone accelerated protein sequence evolution leading to changes in its RNA-binding specificities and cellular localization. While Mbnl2 and Mbnl3 share partially redundant roles in regulating alternative splicing, polyadenylation site usage and, in turn, placenta maturation, Mbnl3 has also acquired novel biological functions. Specifically, Mbnl3 knockout (M3KO) alone results in increased placental growth associated with higher Myc expression. Furthermore, Mbnl3 loss increases fetal resource allocation during limiting conditions, suggesting that location of Mbnl3 on the X chromosome has led to its role in limiting placental growth, favoring the maternal side of the parental genetic conflict.


Asunto(s)
Placenta , Proteínas de Unión al ARN , Empalme Alternativo/genética , Animales , Euterios/genética , Femenino , Placenta/metabolismo , Embarazo , ARN/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
13.
J Immunol ; 211(9): 1426-1437, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37712758

RESUMEN

Allogeneic hematopoietic stem cell transplantation (alloSCT) is, in many clinical settings, the only curative treatment for acute myeloid leukemia (AML). The clinical benefit of alloSCT greatly relies on the graft-versus-leukemia (GVL) effect. However, AML relapse remains the top cause of posttransplant death; this highlights the urgent need to enhance GVL. Studies of human GVL have been hindered by the lack of optimal clinically relevant models. In this article, we report, the successful establishment of a novel (to our knowledge) humanized GVL model system by transplanting clinically paired donor PBMCs and patient AML into MHC class I/II knockout NSG mice. We observed significantly reduced leukemia growth in humanized mice compared with mice that received AML alone, demonstrating a functional GVL effect. Using this model system, we studied human GVL responses against human AML cells in vivo and discovered that AML induced T cell depletion, likely because of increased T cell apoptosis. In addition, AML caused T cell exhaustion manifested by upregulation of inhibitory receptors, increased expression of exhaustion-related transcription factors, and decreased T cell function. Importantly, combined blockade of human T cell-inhibitory pathways effectively reduced leukemia burden and reinvigorated CD8 T cell function in this model system. These data, generated in a highly clinically relevant humanized GVL model, not only demonstrate AML-induced inhibition of alloreactive T cells but also identify promising therapeutic strategies targeting T cell depletion and exhaustion for overcoming GVL failure and treating AML relapse after alloSCT.

14.
Cereb Cortex ; 34(2)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38220573

RESUMEN

Diabetes mellitus (DM) causes damage to the central nervous system, resulting in cognitive impairment. Fibroblast growth factor 21 (FGF21) exhibits the potential to alleviate neurodegeneration. However, the therapeutic effect of intracerebroventricular (i.c.v) FGF21 infusion on diabetes-induced cognitive decline (DICD) and its potential mechanisms remain unclear. In this study, the impact of FGF21 on DICD was explored, and 1H nuclear magnetic resonance (NMR)-based metabolomics plus 13C NMR spectroscopy in combine with intravenous [1-13C]-glucose infusion were used to investigate the underlying metabolic mechanism. Results revealed that i.c.v FGF21 infusion effectively improved learning and memory performance of DICD mice; neuron loss and apoptosis in hippocampus and cortex were significantly blocked, suggesting a potential neuroprotective role of FGF21 in DICD. Metabolomics results revealed that FGF21 modulated DICD metabolic alterations related to glucose and neurotransmitter metabolism, which are characterized by distinct recovered enrichment of [3-13C]-lactate, [3-13C]-aspartate, [4-13C]-glutamine, [3-13C]-glutamine, [4-13C]-glutamate, and [4-13C]- γ-aminobutyric acid (GABA) from [1-13C]-glucose. Moreover, diabetes-induced neuron injury and metabolic dysfunctions might be mediated by PI3K/AKT/GSK-3ß signaling pathway inactivation in the hippocampus and cortex, which were activated by i.c.v injection of FGF21. These findings indicate that i.c.v FGF21 infusion exerts its neuroprotective effect on DICD by remodeling cerebral glucose and neurotransmitter metabolism by activating the PI3K/AKT/GSK-3ß signaling pathway.


Asunto(s)
Disfunción Cognitiva , Diabetes Mellitus , Factores de Crecimiento de Fibroblastos , Ratones , Animales , Glutamina/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas , Ácido Glutámico/metabolismo , Glucosa/metabolismo , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/etiología , Neurotransmisores
15.
Mol Cell ; 65(3): 539-553.e7, 2017 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-28157508

RESUMEN

Networks of coordinated alternative splicing (AS) events play critical roles in development and disease. However, a comprehensive knowledge of the factors that regulate these networks is lacking. We describe a high-throughput system for systematically linking trans-acting factors to endogenous RNA regulatory events. Using this system, we identify hundreds of factors associated with diverse regulatory layers that positively or negatively control AS events linked to cell fate. Remarkably, more than one-third of the regulators are transcription factors. Further analyses of the zinc finger protein Zfp871 and BTB/POZ domain transcription factor Nacc1, which regulate neural and stem cell AS programs, respectively, reveal roles in controlling the expression of specific splicing regulators. Surprisingly, these proteins also appear to regulate target AS programs via binding RNA. Our results thus uncover a large "missing cache" of splicing regulators among annotated transcription factors, some of which dually regulate AS through direct and indirect mechanisms.


Asunto(s)
Empalme Alternativo , Redes Reguladoras de Genes , Análisis de Secuencia de ARN/métodos , Factores de Transcripción/metabolismo , Animales , Línea Celular , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Células HEK293 , Humanos , Ratones , Neuronas/citología , Neuronas/metabolismo , ARN Mensajero/genética
16.
Gut ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38378250

RESUMEN

OBJECTIVES: To evaluate the association between healthy lifestyle behaviours and the incidence of irritable bowel syndrome (IBS). DESIGN: Population-based prospective cohort study. SETTING: The UK Biobank. PARTICIPANTS: 64 268 adults aged 37 to 73 years who had no IBS diagnosis at baseline were enrolled between 2006 and 2010 and followed up to 2022. MAIN EXPOSURE: The five healthy lifestyle behaviours studied were never smoking, optimal sleep, high level of vigorous physical activity, high dietary quality and moderate alcohol intake. MAIN OUTCOME MEASURE: The incidence of IBS. RESULTS: During a mean follow-up of 12.6 years, 961 (1.5%) incident IBS cases were recorded. Among the 64 268 participants (mean age 55.9 years, 35 342 (55.0%) female, 7604 (11.8%) reported none of the five healthy lifestyle behaviours, 20 662 (32.1%) reported 1 behaviour, 21 901 (34.1%) reported 2 behaviours and 14 101 (21.9%) reported 3 to 5 behaviours at baseline. The multivariable adjusted hazard ratios associated with having 1, 2 and 3 to 5 behaviours for IBS incidence were 0.79 (95% confidence intervals 0.65 to 0.96), 0.64 (0.53 to 0.78) and 0.58 (0.46 to 0.72), respectively (P for trend <0.001). Never smoking (0.86, 0.76 to 0.98, P=0.02), high level of vigorous physical activity (0.83, 0.73 to 0.95, P=0.006) and optimal sleep (0.73, 0.60 to 0.88, P=0.001) demonstrated significant independent inverse associations with IBS incidence. No significant interactions were observed between these associations and age, sex, employment status, geographic location, gastrointestinal infection, endometriosis, family history of IBS or lifestyle behaviours. CONCLUSIONS: Adhering to a higher number of healthy lifestyle behaviours is significantly associated with a lower incidence of IBS in the general population. Our findings suggest the potential of lifestyle modifications as a primary prevention strategy for IBS.

17.
J Neurosci ; 43(17): 3009-3027, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-36898834

RESUMEN

RNA N4-acetylcytidine (ac4C) modification is increasingly recognized as an important layer of gene regulation; however, the involvement of ac4C in pain regulation has not been studied. Here, we report that N-acetyltransferase 10 protein (NAT10; the only known ac4C "writer") contributes to the induction and development of neuropathic pain in an ac4C-dependent manner. Peripheral nerve injury increases the levels of NAT10 expression and overall ac4C in injured dorsal root ganglia (DRGs). This upregulation is triggered by the activation of upstream transcription factor 1 (USF1), a transcription factor that binds to the Nat10 promoter. Knock-down or genetic deletion of NAT10 in the DRG abolishes the gain of ac4C sites in Syt9 mRNA and the augmentation of SYT9 protein, resulting in a marked antinociceptive effect in nerve-injured male mice. Conversely, mimicking NAT10 upregulation in the absence of injury evokes the elevation of Syt9 ac4C and SYT9 protein and induces the genesis of neuropathic-pain-like behaviors. These findings demonstrate that USF1-governed NAT10 regulates neuropathic pain by targeting Syt9 ac4C in peripheral nociceptive sensory neurons. Our findings establish NAT10 as a critical endogenous initiator of nociceptive behavior and a promising new target for treating neuropathic pain.SIGNIFICANCE STATEMENT The cytidine N4-acetylcytidine (ac4C), a new epigenetic RNA modification, is crucial for the translation and stability of mRNA, but its role for chronic pain remains unclear. Here, we demonstrate that N-acetyltransferase 10 (NAT10) acts as ac4C N-acetyltransferase and plays an important role in the development and maintenance of neuropathic pain. NAT10 was upregulated via the activation of the transcription factor upstream transcription factor 1 (USF1) in the injured dorsal root ganglion (DRG) after peripheral nerve injury. Since pharmacological or genetic deleting NAT10 in the DRG attenuated the nerve injury-induced nociceptive hypersensitivities partially through suppressing Syt9 mRNA ac4C and stabilizing SYT9 protein level, NAT10 may serve as an effective and novel therapeutic target for neuropathic pain.


Asunto(s)
Neuralgia , Traumatismos de los Nervios Periféricos , Animales , Masculino , Ratones , Acetiltransferasas/metabolismo , Citidina/farmacología , Citidina/genética , Citidina/metabolismo , Ganglios Espinales/metabolismo , Neuralgia/etiología , Neuralgia/metabolismo , Traumatismos de los Nervios Periféricos/complicaciones , Traumatismos de los Nervios Periféricos/metabolismo , ARN , ARN Mensajero/metabolismo , Células Receptoras Sensoriales/metabolismo , Factores de Transcripción/metabolismo
18.
J Cell Mol Med ; 28(12): e18449, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38924214

RESUMEN

Mitochondrial dynamics has emerged as an important target for neuronal protection after cerebral ischaemia/reperfusion. Therefore, the aim of this study was to investigate the mechanism by which ARMC10 regulation of mitochondrial dynamics affects mitochondrial function involved in ischaemic stroke (IS). Mitochondrial morphology was detected by laser scanning confocal microscopy (LSCM), and mitochondrial ultrastructural alterations were detected by electron microscopy. The expression of mitochondrial dynamics-related genes Drp1, Mfn1, Mfn2, Fis1, OPA1 and ARMC10 and downstream target genes c-Myc, CyclinD1 and AXIN2 was detected by RT-qPCR. Western blot was used to detect the protein expression of ß-catenin, GSK-3ß, p-GSK-3ß, Bcl-2 and Bax. DCFH-DA fluorescent probe was to detect the effect of ARMC10 on mitochondrial ROS level, Annexin V-FITC fluorescent probe was to detect the effect of ARMC10 on apoptosis, and ATP assay kit was to detect the effect of ARMC10 on ATP production. Mitochondrial dynamics was dysregulated in clinical IS samples and in the OGD/R cell model, and the relative expression of ARMC10 gene was significantly decreased in IS group (p < 0.05). Knockdown and overexpression of ARMC10 could affect mitochondrial dynamics, mitochondrial function and neuronal apoptosis. Agonist and inhibitor affected mitochondrial function and neuronal apoptosis by targeting Wnt/ß-Catenin signal pathway. In the OGD/R model, ARMC10 affected mitochondrial function and neuronal apoptosis through the mechanism that regulates Wnt/ß-catenin signalling pathway. ARMC10 regulates mitochondrial dynamics and protects mitochondrial function by activating Wnt/ß-catenin signalling pathway, to exert neuroprotective effects.


Asunto(s)
Apoptosis , Proteínas del Dominio Armadillo , Accidente Cerebrovascular Isquémico , Mitocondrias , Dinámicas Mitocondriales , Vía de Señalización Wnt , Mitocondrias/metabolismo , Humanos , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/genética , Accidente Cerebrovascular Isquémico/patología , Proteínas del Dominio Armadillo/metabolismo , Proteínas del Dominio Armadillo/genética , Masculino , beta Catenina/metabolismo , beta Catenina/genética , Especies Reactivas de Oxígeno/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/genética , Isquemia Encefálica/patología , Animales
19.
Plant J ; 113(4): 677-697, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36534087

RESUMEN

Salt stress is one of the major causes of reduced crop production, limiting agricultural development globally. Plants have evolved with complex systems to maintain the balance between growth and stress responses, where signaling pathways such as hormone signaling play key roles. Recent studies revealed that hormones are modulated by microRNAs (miRNAs). Previously, two sweet sorghum (Sorghum bicolor) inbred lines with different salt tolerance were identified: the salt-tolerant M-81E and the salt-sensitive Roma. The levels of endogenous hormones in M-81E and Roma varied differently under salt stress, showing a different balance between growth and stress responses. miRNA and degradome sequencing showed that the expression of many upstream transcription factors regulating signal transduction and hormone-responsive genes was directly induced by differentially expressed miRNAs, whose levels were very different between the two sweet sorghum lines. Furthermore, the effects of representative miRNAs on salt tolerance in sorghum were verified through a transformation system mediated by Agrobacterium rhizogenes. Also, miR-6225-5p reduced the level of Ca2+ in the miR-6225-5p-overexpressing line by inhibiting the expression of the Ca2+ uptake gene SbGLR3.1 in the root epidermis and affected salt tolerance in sorghum. This study provides evidence for miRNA-mediated growth and stress responses in sweet sorghum.


Asunto(s)
MicroARNs , Sorghum , MicroARNs/genética , MicroARNs/metabolismo , Sorghum/metabolismo , Estrés Fisiológico/genética , Estrés Salino/genética , Grano Comestible/genética , Hormonas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética
20.
J Am Chem Soc ; 146(1): 868-877, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38153404

RESUMEN

Great effort has been made to encapsulate or coat living mammalian cells for a variety of applications ranging from diabetes treatment to three-dimensional printing. However, no study has reported the synthesis of a biomimetic bacterial capsule to display high-affinity aptamers on the cell surface for enhanced cell recognition. Therefore, we synthesized an ultrathin alginate-polylysine coating to display aptamers on the surface of living cells with natural killer (NK) cells as a model. The results show that this coating-mediated aptamer display is more stable than direct cholesterol insertion into the lipid bilayer. The half-life of the aptamer on the cell surface can be increased from less than 1.5 to over 20 h. NK cells coated with the biomimetic bacterial capsule exhibit a high efficiency in recognizing and killing target cells. Therefore, this work has demonstrated a promising cell coating method for the display of aptamers for enhanced cell recognition.


Asunto(s)
Aptámeros de Nucleótidos , Animales , Aptámeros de Nucleótidos/metabolismo , Cápsulas Bacterianas/metabolismo , Biomimética , Membrana Celular/metabolismo , Técnica SELEX de Producción de Aptámeros/métodos , Mamíferos/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA